Check valve with restricted bypass flow

ABSTRACT

A FLUID FLOW CHECK VALVE INCLUDING A CASING HAVING A FLOW APERTURE ON EACH END, A FLOATING VALVE MEMBER PREVENTING A FREE FLUID FLOW IN ONE DIRECTION THROUGH ONE END AND PERMITTING A FREE FLUID FLOW THROUGH THE OTHER END, A RESTRICTED FLUID FLOW BYPASSES THE VALVE MEMBER TO PERMIT A RESTRICTED FLOW WHEN THE VALVE MEMBER IS IN ITS FLOW PREVENTING POSITION.

March 23, 1971 GRAHAM ETAL 3,572,377

CHECK-VALVE WITH RESTRICTED BYPASS FLOW Original Filed June 6, 1968 2Sheets-Sheet 1 FIG.| l2 FIG-2 I4 I4 24 lo 24 I2 I6 l6 l fl H32 ,fi/ 3636 H A A K I Q Q a 3% 3K h 3O\\ 4 11 I I I! HIY I8 22 2 6 ls mvmons,

MARVIN MGRAHAM LAUREN D. HASKINS BY W X. p

ATTORNEY 23, M GR ETAL CHECK-VALVE WITH RESTRICTED BYPASS FLOW OriginalFiled June 6, 1968 2 Sheets-Sheet 2 no I 1- us I I l "I 8 FIG. 9

MARVIN M.GRAHAM LAUREN D. HASKINS Ma -0m ATTORNEY nwnvraes United StatesPatent 3,572,377 CHECK VALVE WITH RESTRICTED BYPASS FLOW Marvin M.Graham, San Pedro, and Lauren D. Haskins, Long Beach, Calif., assignorsto Robertshaw Controls Company, Richmond, Va. Original application June6, 1968, Ser. No. 734,926. Divided and this application Mar. 12, 1970,Ser.

Int. Cl. F16k 15/02 U.S. Cl. 137-513.7 8 Claims ABSTRACT OF THEDISCLOSURE A fluid flow check valve including a casing having a flowaperture on each end, a floating valve member preventing a free fluidflow in one direction through one end and permitting a free fluid flowthrough the other end; a restricted fluid flow bypasses the valve memberto permit a restricted flow when the valve member is in its flowpreventing position.

CROSS-REFERENCE TO RELATED APPLICATION This application is a divisionapplication of our pending application Ser. No. 734,926, filed June 6,1968.

BACKGROUND OF THE INVENTION This invention relates to flow controlvalves, and in particular, to a check valve which permits anunrestricted flow in one direction and a restricted flow in the oppositedirection.

Conventionl prior art devices have utilized check valves with restrictedpassages for flow paths; however, such devices have been ineffectivebecause the cross sectional flow area of the restricted orifice had tobe limited to design dimensions which enhanced the possibility ofcloggmg.

SUMMARY OF THE INVENTION It is, therefore, an object of the presentinvention to provide a check valve with a restricted flow path that iselongated to accomplish the function of flow restriction.

Another object of the present invention is to assemble a free floatingvalve member in a casing that does not require any particularorientation for its operation.

The present invention is summarized in the assembly of a check valveincluding a hollow casing having a peripheral wall, transverse memberson each end of the casing attached to the peripheral wall, flow aperturemeans in each transverse member, valve means in the casing movablebetween the transverse members to define flow permitting and flowpreventing positions, bypass means establishing a fluid flow bypassingthe valve means when in its flow preventing position, and a flowrestricting passage forming a part of the bypass means to restrict thebypass fluid flow.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross section of a checkvalve embodying the present invention;

FIG. 2 is a cross section similar to FIG. 1 but showing its valve memberin a second controlling position;

FIG. 3 is a top plan view of FIG. 1;

FIG. 4 is a top plan view of a detail of FIG. 1;

FIG. 5 is a bottom plan view of a detail of FIG. 1;

FIG. 6 is a bottom plan view similar to FIG. 5 but showing amodification thereof;

FIG. 7 is a bottom plan view similar to FIG. 5 but showing a secondmodification;

FIG. 8 is a cross section of a check valve similar to FIG. 1 but showinga modification thereof;

3,572,377 Patented Mar. 23, 1971 FIG. 12 is a top plan view of a detailof FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As is shown in FIGS. 1 and 2,an embodiment of the present invention includes an inverted cup-shapedcontamer or casing 10 having a flow aperture 12 in a transverse memberdefining its fiat wall; a plurality of inwardly directed dimples orbosses 14 in such wall are circumferentially spaced around the aperture12. The peripheral or cylindrical wall of the casing 10 is deformedadjacent the flat end wall to define an annular shoulder 16 while thelip of the cylinder wall has an inwardly bent peripheral flange 18. Aflat plate member 20 having a central bore or flow aperture 22 is seatedin the casing 10 and rests on the flange 18. A thin, relatively lightfree floating disc 24 acts as a valve and is disposed in the casing 10underneath the dimples 14 for a purpose to be described more fullyhereinafter.

A flat plate member in the form of a disc 30 having a central bore 32rests on the plate 20 with the bores 22 and 32 being aligned. The platesor discs 20 and 30 are fixed in the casing 10 by being peripherallyclamped between the annular shoulder 16 and the peripheral flange 18whereby such plates as a unit define a lower transverse member for thecasing 10. As is illustrated in FIG. 5, the disc 30 is provided with asurface recess in the form of a spiral groove 34 extending between theaperture 32 and one or more peripheral recesses 36 cut out of thecircumferential wall of the disc 30. The diameter of the flexible valvedisc 24 is the same as the inner diameter of the disc 30, which innerdiameter is equal to the outer diameter of the disc 30 minus thedimension of the recess 36, Each recess 36 has an arcuate shape and isof greater depth than the width of the annular shoulder 16; with such anarrangement, communication is continuously established between the bore22 and the casing aperture 12. The grooved surface of disc 30 is insurface contact with the disc 20 which thus forms one wall of the spiralgroove 34.

In operation of the above check valve, relatively free flow is obtainedin the upward direction as shown in FIG. 2 wherein the pressure of thefluid flow displaces the thin valve member 24 from the disc 30 and intocontact with the dimples 14 underneath the upper transverse member ofthe casing 10. The fluid flow thus proceeds unrestricted through a pathtraced from the bores 22 and 32 through the chamber defined by the valvemember 24 and the corresponding surface of the disc 30, thence aroundthe periphery of the valve member 24 and across the top surface thereofbetween the dimples 14 to the flow aperture 12.

FIG. 1 represents the flow path in the downward direction wherein thepressure of the fluid flow causes the thin valve member 24 to lie flaton the top of disc 30 and prevent a fluid flow into the top of the discbore 3 2. The fluid flow thus proceeds in a restricted path traced fromthe aperture 12 into the chamber defined by the top of the thin valvemember 24, around the periphery of the valve member 24, through therecess 36 and the spiral groove 34 to the aligned bores 32 and 22. Therelatively long path of the grooved restrictor 34 enables a higherdegree of restriction than could be obtained with a simple orifice ofthe same cross sectional flow area. The restricting feature is furtherenhanced by the change of directions which the fluid flow must undergo;e.g., the downward vertical direction of the fluid flow changesperpendicularly to the edge of the valve member 24, thence to a downwardvertical direction through the recess 36 whence it again changesperpendicularly to the plane of the groove 34, after which it againchanges to a downward vertical direction through the bores 32 and 22.

It should be noted that the thin valve member 24 is a free floatingvalve which is moved by pressure between the dimples 14 and the topsurface of the disc 30. Accordingly, even though FIGS. 1 and 2 have beendescribed in terms of upward and downward directions, the entireassembly constitutes a capsule which may be oriented in any direction,i.e., the capsule may be inverted or it may be mounted on its sidebecause the tin valve member 24 is not gravity responsive.

The amount of flow restriction increases with the length of therestricting groove. In addition, a groove configuration with a rapid orsubstantial change in radius may also be used to increase therestriction for an equivalent cross sectional flow area. In themodification of FIG. 6, the end plate or transverse member in the formof a disc has a central bore 42 (alignable with disc bore 22 of FIG. 1),and a restricting groove 44 establishing communication between aperipheral recess 46 and the bore 42. The groove 44 consists ofconcentrically spaced recesses whereby the flow direction from theperipheral recess 46 undergoes a 180 reversal and then a change leadingto the central bore 42. The disc 40 may replace the disc 30 of FIGS. 1and 2 and since its operation in the capsule 10 is similar to that ofFIGS. 1 and 2, a description of its sequence of operation is beingomitted for the sake of brevity.

Similarly, the operation of the modification of FIG. 7 is being omitted,wherein the second plate member in the form of a disc 50 has a centralbore 52 (alignable with disc bore 22 of FIG. 1), and a restrictinggroove 54 establishing communication between a peripheral recess 56 anda bore 52. The groove consists of a generally annular zigzagconfiguration whereby the flow direction has a plurality of abruptchanges. Thus, the disc 50 in FIG. 7 has a grooved restrictor 54 thatprovides a higher degree of restriction for equal length and crosssection than the grooved restrictor 44 in disc 40; similarly, thegrooved restrictor 44 provides a higher degree of restriction for equallength and cross section than the grooved restrictor 34 in the disc 30.

FIGS. 8-12 illustrate a modification of the check valve casing and inorder to facilitate its correlation with FIGS. 1-5, the same referencenumerals with added are utilized for similar structural parts. Forexample, the embodiment shown in FIGS. 8-12 includes a cup-shapedcontainer or casing having a transverse member 111 with a centrallydisposed flow aperture 112. A plurality of inwardly directed dimples orbosses 114 in the transverse plate 111 are circumferentially spacedaround the aperture 112; a similar number of similarly spaced dimples orbosses 115 are outwardly directed from the surface of the transverseplate 111 whereby the plate may be assembled with either surfacedirected toward the interior of the casing 110. The peripheral orcylindrical wall of the casing 110 has an inner surface provided with anannular shoulder 116 on which the transverse plate 111 is seated; aplurality of inwardly directed, hemispherical lugs 118 are equallyspaced about the inner periphery of the cylindrical wall to definefastening means for the transverse plate 111. Since the casing 110 ismade of a plastic material the transverse plate 111 is easily insertedby merely pressing downwardly past the lugs 118. A second flat platemember 120 is disposed in the bottom of the casing 110 and has a centralhollow annulus defining a flow aperture 122, the lowermost portion ofwhich is flared outwardly at 123 to secure the plate 122 in a fixedposition.

A thin, relatively light free floating disc 124 acts as a valve and isdisposed in the casing for movement between a flow preventing positionwhen it is seated on the top of 4 plate 120 (FIG. 8) and a flowpermitting position when it engages the bosses 114 (FIG. 9).

In the embodiments of FIGS. 8-12, the lowermost transverse member isintegrally formed with the cylindrical wall of the casing 110 to definea cup-shaped configuration. The central portion of the transverse member130 has an opening 132 which receives the cylindrical portion 122 of theplate 120. Radially spaced from the opening 132, the transverse member130' has an opening 133, the innermost portion of which communicateswith one end of a flow restriction groove 134 integrally formed in thetop surface of the transverse member 130. The other end of groove 134has a peripheral opening 136 (FIG. 11) which communicates with thechamber that houses the valve member 124. The diameter of the valve disc124 and the diameter of the plate 120 are each smaller than the diameterof the valve chamber; accordingly, communication is continuouslyestablished between the flow aperture 112 and the opening 133 to definea restricted flow which bypasses the valve disc 124.

The operation of the embodiment illustrated in FIGS. 8-12 issubstantially the same as that described above in FIGS. 1 and 2, exceptthat the restricted bypass flow has a separate outlet 133. A sepecificdescription of a sequence of operation of FIGS. 8 and 9 is :thus deemedunnecessary and is being omitted for the sake of brevity. It should benoted however that the specific groove recess 134 shown in FIG. 11 maybe replaced with any of the specific modifications of the restrictinggroove, such as 34 in FIG. 5, 44 in FIG. 6 and 54 in FIG. 7.

Inasmuch as the present invention is subject to many modifications,variations and changes in detail, it is intended that all mattercontained in the foregoing description or shown on the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:

1. A check valve comprising a casing having a peripheral wall and atransverse wall joined thereto,

means defining a flow aperture in said transverse wall,

valve engaging means on said transverse wall adjacent said flowaperture,

3. pair of plates mounted in juxtaposed relation in said casing,

bore means in said plates to permit a fluid flow therethrough,

a floating valve member in said casing movable between first and secondpositions in response to fluid flow pressure,

said first position defining an unrestricted flow condition when saidvalve member contacts said valve engaging means,

said second position defining a restricted flow condition when saidvalve member contacts one of said plates, and r means defining arestricted flow path through one of said plates whereby a flow to saidbore means bypasses said valve member.

2. The invention as recited in claim 1 wherein said bore means comprisesa central bore in each of said plates and being aligned with each other.

3. The invention as recited in claim 2 wherein said means defining arestricted flow path includes a peripheral recess in one of said platesand an elongated passage means in said one plate establishingcommunication between said recess and the central bore of said oneplate.

4. The invention as recited in claim 3 wherein said elongated passagemeans is disposed in a plane transverse to a plane defined by saidcentral bores.

5. The invention as recited in claim 3 wherein said elongated passagemeans comprises a spiral groove.

6. The invention as recited in claim 3 wherein said elongated passagemeans comprises concentrically spaced recesses joined together to definedirection changing means to increase flow restriction therethrough.

7. The invention as recited in claim 3 wherein said elongated passagemeans comprises a generally annular zigzag configuration.

8. The invention as recited in claim 4 wherein said pair of platescomprises a pair of fiat discs and wherein said peripheral wall includesan annular shoulder engaging a peripheral portion of one of said discsand an annular flange engaging a peripheral portion of the other of saiddiscs,

References Cited UNITED STATES PATENTS 1,187,537 6/1916 Loomis 137-513.51,505,695 8/1924 Boyd 137533.l9 2,021,079 11/1935 Mittendorf 138-423,375,855 4/1968 Deeks 13842 3,439,660 4/1969 Lesher 138-42 WILLIAM F.ODEA, Primary Examiner W. H. WRIGHT, Assistant Examiner US. 01. X.R,137-4133, 533.19

